Facile synthesis of NH2-MIL-53(Al)@RhB as a dual-emitting “on-off-on” probe for the detection of Fe3+ and L-ascorbic acid

The identification of L-ascorbic acid (AA) and iron ion (Fe3+) is important for clinicopathological analyses. Herein, a dual-emitting fluorescent “on-off-on” sensor based on NH2-MIL-53(Al)/RhB was first constructed for the simultaneous detection of Fe3+ and AA. The sensor could quantify Fe3+ with a limit of detection of 0.31 µM and AA with a limit of detection of 0.30 µM, respectively. The excellent sensing performance could be ascribed to ion exchange and redox reaction. In addition, the practical application of this platform showed acceptable relative recoveries for Fe3+ (89–102%) and AA (97–105%), and precisions were also achieved (relative standard deviation≤1.9%, n=3). These results indicated that the presented sensor can be applied to detect the Fe3+ and AA in real samples.